The production of low volume sheet metal components is a difficult balancing act of non-recurrent equipment cost and final component sale value. Industry sectors in which low volume components are commonplace include aerospace, marine and architecture. Each of these industry sectors presents unique challenges that are a combination of the component material, tolerances required and number of repeat components. While Aerospace utilises high strength metals that must meet stringent dimensional tolerances manufactured in reasonable batch numbers, architecture typically employs comparatively lower strength metals with wider dimensional tolerances and often single component manufacture.
Traditional manufacturing methods employed in the production of components for these industry sectors often utilise fixed tools and large complex machines that require substantial foundations. Tooling costs can be reduced through the use of processes such as stretch forming where, depending upon the component shape, only a single male tool is required. Costs can be further reduced through the reuse of tooling by machining the tool multiple times. Nevertheless, such innovations are limited in the achievable cost savings.
One possible alternative is reconfigurable pin tool technology, where a forming surface is defined by an array of height adjustable pins, typically having a flexible interpolator sheet located between the pins and the work piece, wherein the heights of the pins can be adjusted to vary the shape of the forming surface. The use of reconfigurable pin tool technology in stretch forming has been the subject of much research over the past 20 years. However, most prior art attempts to exploit this technology have resulted in complex and expensive incarnations that, while technically brilliant, have been commercially flawed. In addition, the use of complex stretch forming machines to stretch a sheet metal blank over the forming surface have further increased the overall production cost and have therefore limited the adoption of reconfigurable pin tool technology.